Fig. 1

C. churrovis cultured on reed canary grass covers plant biomass surface in the absence of a rhizoid network. Helium ion microscopy (A, B) of C. churrovis grown on crude plant material (reed canary grass) highlights the spherical sporangia and lack of extensive mycelial network. The fungus shows a wide range of size of sporangia, likely due to different phases of the growth cycle. In A, C, the reed canary grass is visible and C. churrovis sporangia are attached to it via small “holdfasts.” Images B, D show a small particle of plant material completely covered in sporangia. Image B also shows a ruptured sporangium that has broken open to let out the motile zoospores as part of the gut fungal reproductive cycle